Royal engagement provides much-needed shine for gloomy Britain

London: "Good to see some cheery news," Vince Cable, the leader of the Liberal Democrats party said as news of Prince Harry's engagement to American actress Meghan Markle was announced.

Cable's tweet is telling of the national mood in Britain as winter bites and 2017 comes to a close.

Politically, the year has been marked by instability: Theresa May's snap election and near defeat, the ongoing uncertainty over Brexit as negotiations with the European Union broke down and the horrific spate of terror attacks in London and Manchester.

But Monday's royal engagement set the scene for a chirpier spring. In April, Kate is due to give birth to her third child with Prince William, the second-in-line to the throne.

Around that time, Prince Harry will marry Markle, an American, mixed-race divorcee who is an unconventional bride for the once-stuffy royal family, but one who undoubtedly brings to the relationship an element of glamour the world's tabloids can gush over for decades.

And Britons are hoping they'll be given a public holiday, to celebrate the big day with the couple.

"Britain is very uncertain at the moment - we've got Brexit, an unstable government, a very polarised political landscape and an insurgent Labour party," 30-year old Matt Jones from Nottingham told Fairfax Media on the train home from London on Monday.

"I actually think a royal wedding will do us good," he said. "It will give us a chance to forget our worries for a while and just relax.

"That's what happened during William's wedding and during the Olympics and I think even critics of the royal family respect Harry, especially after what he's been through."

Dan Horton, 44, from Darlington in England's north-east said with changes at the top of the monarchy - Prince Philip is no longer accepting public duties and the Queen has begun to hand over some of hers to her son and grandchildren - it was nice to hear some good news.

"It's lovely to hear some uplifting, good news that gives us all hope for the future," he said. "It gives us hope in a world full of atrocities, so even in the darkest moments there can be light."

"It's good to have something on the news rather than Brexit or doom and gloom," agreed Jill from Belfast.

Companies were quick to start cashing in on the goodwill.

"When you hear there's a party in London next spring and flights start at ???16.99...simply reMARKLEable!" tweeted the Irish budget airliner Ryanair.

But Ben Page, chief executive of IPSOS Mori, says the effects of major events on the national mood can often be overstated.

"To be honest, we think these things - royal weddings, winning or losing World Cup etc - have only a short term effect if any and don't shift the national mood ultimately, although this doesn't mean people don't enjoy them," he said.

And he said it was significant that Harry was fifth-in-line to the throne and unlikely to ever be the monarch.

"Although 77 per cent of the British public are monarchists, Harry is not heir to the throne so it is nice to have, but not a 'game changer'," he said

He said the eventual death of the Queen would be the royal event that would change the national mood.

But what is certain is that the wedding of Princess Diana's second son will generate huge worldwide interest, which can be calculated in hard dollar terms.

Brand Finance released a report last week to coincide with the 70th anniversary of the Queen's marriage to Prince Philip, calculating the worth of the royal family to be ??67.5 billion ($118 billion).

Spokesman Konrad Jagodzinski said the wedding could add "hundreds of millions" in value to the monarchy in boosted tourist visits to the UK and related merchandise.

"It was similar in 2011 when the royal wedding of the Duke and Duchess of Cambridge took place. It can be expected that the royal wedding could have a very similar effect on the UK economy next year," he said.

"In the sense of Meghan Markle there is a chance that this effect will be even bigger as she's already got a brand of her own as an actress," he said.

But he said it would depend on whether the couple opted for a public or private wedding and if a bank holiday was granted.

"If so, that can actually come at a cost to the economy because people are not at work and that obviously means less value is generated on that day," he said.

"If it is a public wedding, if it is a public occasion then that definitely means it's going to bring a lot of value to the UK economy, through tourism, through hotel bookings, through merchandise sales and so on."

Mark Crowe, Brand Finance's managing director in Australia, believes there will be flow on effects at home.

"The monarchy's popularity is increasing thanks to the younger royals, who are more progressive and less formal in their public appearances and the way they carry out their duties," he said.

"This more relaxed approach appeals to many Australians regardless of their views on a republic.

"Furthermore, any visit by the newlyweds to the Australian shores would provide a significant boost to Australia's tourism economy," he said.

Prince Harry is due in Australia in October next year for the 2018 Invictus Games, an international sporting competition he founded for wounded war veterans.

Significantly, it was at the 2017 games in Toronto where he made his first public outing with Ms Markle. The couple were photographed holding hands for the first time since their relationship was confirmed.

Whether it will be their first official visit abroad remains to be seen. First, there's a wedding to plan.